The overarching goal of this competing renewal application is to examine the linkage between child and adolescent predictors and young adult alcohol use and problems using longitudinal data from the Tween to Teen Project, a community sample of 452 European-American and African-American 8- and 10-year-old children and their families randomly selected from Allegheny County (PA). By the end of the 10th year of funding, 14 waves will have been collected on the two age cohorts, encompassing ages 8-16 for the younger cohort and ages 10-18 for the older cohort. This renewal will support the collection of age-18 data on the younger cohort and age-21 data on both age cohorts. The Tween to Teen Project is unique in its attention to the development of both alcohol-specific and general risk factors for the early initiation of drinking and the escalation into problem drinking from middle childhood through middle adolescence. The theoretical framework underlying the research is Problem Behavior Theory (PBT: Jessor &Jessor, 1977), which we have extended downstream into middle childhood and expanded to include greater attention to the parental and peer social environments and their influence on socialization. In addition, variables reflecting behavioral undercontrol, negative affectivity, temperament, and family history of alcohol problems were incorporated in the longitudinal assessments. Retention has been excellent. As of Wave 12, 85 percent of the original sample (384 of 452 families) are still participating. Waves 13 and 14 are ongoing. Specific aims are the following: 1) To describe the trajectories of development on alcohol-specific and general risk factors from middle childhood into young adulthood, comparing trajectories across early-onset drinkers (age 14 or younger), later-onset drinkers (age 15+), and never drinkers;2) To determine the young adult consequences of early-onset drinking in contrast to later-onset drinking using age-21 data;3) To use the personality, social environment, and behavior variables of PBT and the other variables collected in the Tween and Teen phases of data collection as prospective antecedent predictors of young adult alcohol use and alcohol use disorder (AUD) outcomes;and 4) To examine the relationship between growth in alcohol involvement from adolescence into young adulthood and growth in latent constructs reflecting problem behavior proneness in Problem Behavior Theory, as well as constructs reflecting behavioral undercontrol and negative affectivity. Accomplishment of these research aims should enhance understanding of the relationships among early-onset drinking, psychosocial development, and movement into problematic alcohol use in young adulthood. The research should thereby advance prevention efforts by identifying which modifiable risk factors should be targeted for maximum effect in reducing young adult problem drinking. PUBLIC HEALTH RELEVANCE: The proposed research should enhance understanding of the relationships among early-onset drinking, psychosocial development, and movement into problematic alcohol use in young adulthood. The research should thereby advance prevention efforts by identifying which modifiable risk factors should be targeted for maximum effect in reducing young adult problem drinking.